From your description of her description, it does sound potentially concerning. Any cut or laceration, if it becomes infected, does have a potential risk of becoming infected, and furthermore, of leading to sepsis (a infection in the blood).
I can't recommend any treatment besides getting her to an Emergency Department as soon as possible. Epsom salts, or a soak, really shouldn't have any beneficial effect on an infection like this. She really needs to be seen and examined, as soon as possible. She might indeed require antibiotics, and perhaps even intravenous antibiotics; remember, there are MANY antibiotics besides the sulfur-based ones. If an infection that leads to cellulitis (localized infection within the tissues) or sepsis isn't treated this can most certainly lead to substantial disability if not death.
One thing to consider, is that most communities and Emergency Departments have funds available to provide care to people who are without income and insurance. There may be one ED in a community that does provide this, while others don't, so you might need to inquire. But everyone is entitled to emergency treatment for injuries, and potentially life-threatening ones, so she should go.
Encourage her, and hopefully you will be able to get her care provided at reduced or even no cost. Then, she has nothing left to lose and everything to gain.
I hope this helps. Please let me know if you have any further questions - I'm more than happy to help and I'll be available all day. Take care - Dr. Fay
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